The range of materials that can be used in 3D printing is constantly expanding, but still many thermoplastics are either very difficult to tame while working, or still impossible. Among them, we can mention polycarbonate (PC), poly methylene oxide (POM), polyamide 6 (PA6), polyethylene (PE) or teflon (PTFE). Until recently, this group also included polypropylene (PP), but recently very great progress has been made in this area.
Polish filament manufacturer – Fiberlogy introduced this material to its offer at the end of last year, and we have had the opportunity to work with it for several months, achieving fantastic results. In this article, we will present the specifics of working with this filament, which is perfect where we are looking for durable, but at the same time slightly flexible and springy aplications.
The material is printed on three models of 3D printers: Zortrax M200, Zortrax Inventure and ZMorph VX. While in terms of quality, we achieve comparable results on each of the devices, in terms of efficiency and dealing with technical nuances, ZMorph is the best in this respect, about which I write more below. In the end, contrary to initial ideas, working with PP is quite simple and theoretically possible even on cheap, amateur 3D printers – it all comes down to the issue of settings and design solutions that a given device is equipped with.
But let’s start with the material itself. Polypropylene (PP) is one of the most popular plastics in the industry, used in industries such as automotive, medicine and the packaging. It i characterized by high flexibility and elasticity, resistance to chemical compounds, durability and impact strength. The tensile strength makes polypropylene suitable for the production of elements requiring durability while maintaining flexibility: closed containers or handles.
Fiberlogy’s 3D printing material is available in one diameter: 1.75 mm and as many as 9 color variants (black, blue, gray, graphite, green, orange, red, yellow and natural / ivory). There is 0.75 kg of material on the spool.
In principle, 3D printing with PP does not differ much from working with flexible materials such as TPU or FLEX and such 3D printing profiles should be set (and possibly modified). The manufacturer’s recommended 3D printing temperature is 220-250°C. As for the heated bed issue, it’s quite an interesting thing – Fiberlogy suggests a range of 0°C to 80°C, which might be a bit confusing? In fact, if you want to print without using a specific solution (which I write about below), it is necessary to strongly heat the printbed, which is additionally covered with some adhesive.
Our experience with the Zortrax M200 (perforated bed) and Inventure (plastic bed) prove that too low temperature of the printbed and lack of adhesive coating creates a high risk of peeling off larger prints during the work. It looks better on ZMorph, where we are dealing with a glass, however, also here it is necessary to cover its surface with an adhesive.
Fortunately, our colleagues from Fiberlogy have certainly suggested a solution that is trivial in its simplicity, which completely eliminates this problem (see next paragraph).
As PP is flexible, it should not be printed at too high speeds and can be problematic with 3D printers equipped with a Bowden type extruder (i.e. an extruder mounted in a different place on the 3D printer than on the carriage leading the print head in the axes). We did several trials on the Creality CR-10S and most of them were unsuccessful – the material jammed in the extruder or the section connecting it to the printhead. These were not problems condemning this type of solution to total rejection, just having the option to work with 3D printers with direct extruders (i.e. installed above the print head) we chose the easier solution.
The ZMorph VX is perfect here, where the distance from the material spool to the extruder and the print head is small, which minimizes the risk of the filament curling in the system.
As for the colors of the material, so far we have worked with natural, black, gray, graphite and blue. The only problems we encountered (only on Zortraxes) were blocking of the gray material in the printhead. The aesthetics of the prints made of gray material was also by far the weakest. In terms of the ease of work ratio to the quality of the obtained prints, PP is best presented in natural colors (i.e. without any dye), black and blue.
There is a very simple and ingenious solution for this: on the table of the 3D printer you should stick an ordinary, transparent office tape, which is also made of PP. Printouts stick to it perfectly and heating the working table is completely unnecessary – and not even recommended, because after finishing work you have to wait a long time for the working table to cool down; on a cold table, the printout can be removed (peeled off) immediately.
The only thing you need to pay attention to is evenly stuck the table with tape – any deformations, thickenings resulting from the overlapping of one tape on the other will be visible on the lower surface of the printout.
This is what 3D prints made of PP look like…
Everyone interested in 3D printing from polypropylene (PP), please contact us and send us 3D models – we will be happy to conduct appropriate tests.